reset: dra7: Add a reset driver
Add a reset driver to bring IPs out of reset.
Signed-off-by: Keerthy <j-keerthy@ti.com>
[Amjad: reset_ops structure member "free" has been renamed to "rfree",
use the latter instead]
Signed-off-by: Amjad Ouled-Ameur <aouledameur@baylibre.com>
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index d73daf5..b577141 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -206,4 +206,10 @@
passing request via Xilinx firmware interface to TF-A and PMU
firmware.
+config RESET_DRA7
+ bool "Support for TI's DRA7 Reset driver"
+ depends on DM_RESET
+ help
+ Support for TI DRA7-RESET subsystem. Basic Assert/Deassert
+ is supported.
endmenu
diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index d69486b..97e3a78 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -30,3 +30,4 @@
obj-$(CONFIG_RESET_RASPBERRYPI) += reset-raspberrypi.o
obj-$(CONFIG_RESET_SCMI) += reset-scmi.o
obj-$(CONFIG_RESET_ZYNQMP) += reset-zynqmp.o
+obj-$(CONFIG_RESET_DRA7) += reset-dra7.o
diff --git a/drivers/reset/reset-dra7.c b/drivers/reset/reset-dra7.c
new file mode 100644
index 0000000..585f832
--- /dev/null
+++ b/drivers/reset/reset-dra7.c
@@ -0,0 +1,97 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Texas Instruments DRA7 reset driver
+ *
+ * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
+ * Author: Keerthy <j-keerthy@ti.com>
+ */
+
+#include <asm/io.h>
+#include <common.h>
+#include <dm.h>
+#include <reset-uclass.h>
+#include <dm/device_compat.h>
+
+struct dra7_reset_priv {
+ u32 rstctrl;
+ u32 rstst;
+ u8 nreset;
+};
+
+static int dra7_reset_request(struct reset_ctl *reset_ctl)
+{
+ return 0;
+}
+
+static int dra7_reset_free(struct reset_ctl *reset_ctl)
+{
+ return 0;
+}
+
+static inline void dra7_reset_rmw(u32 addr, u32 value, u32 mask)
+{
+ writel(((readl(addr) & (~mask)) | (value & mask)), addr);
+}
+
+static int dra7_reset_deassert(struct reset_ctl *reset_ctl)
+{
+ struct dra7_reset_priv *priv = dev_get_priv(reset_ctl->dev);
+ int mask = 1 << reset_ctl->id;
+
+ if (reset_ctl->id < 0 || reset_ctl->id >= priv->nreset)
+ return -EINVAL;
+
+ dra7_reset_rmw(priv->rstctrl, 0x0, mask);
+
+ while ((readl(priv->rstst) & mask) != mask)
+ ;
+
+ return 0;
+}
+
+static int dra7_reset_assert(struct reset_ctl *reset_ctl)
+{
+ struct dra7_reset_priv *priv = dev_get_priv(reset_ctl->dev);
+ int mask = 1 << reset_ctl->id;
+
+ if (reset_ctl->id < 0 || reset_ctl->id >= priv->nreset)
+ return -EINVAL;
+
+ dra7_reset_rmw(priv->rstctrl, mask, 0x0);
+
+ return 0;
+}
+
+struct reset_ops dra7_reset_ops = {
+ .request = dra7_reset_request,
+ .rfree = dra7_reset_free,
+ .rst_assert = dra7_reset_assert,
+ .rst_deassert = dra7_reset_deassert,
+};
+
+static const struct udevice_id dra7_reset_ids[] = {
+ { .compatible = "ti,dra7-reset" },
+ { }
+};
+
+static int dra7_reset_probe(struct udevice *dev)
+{
+ struct dra7_reset_priv *priv = dev_get_priv(dev);
+
+ priv->rstctrl = dev_read_addr(dev);
+ priv->rstst = priv->rstctrl + 0x4;
+ priv->nreset = dev_read_u32_default(dev, "ti,nresets", 1);
+
+ dev_info(dev, "dra7-reset successfully probed %s\n", dev->name);
+
+ return 0;
+}
+
+U_BOOT_DRIVER(dra7_reset) = {
+ .name = "dra7_reset",
+ .id = UCLASS_RESET,
+ .of_match = dra7_reset_ids,
+ .probe = dra7_reset_probe,
+ .ops = &dra7_reset_ops,
+ .priv_auto = sizeof(struct dra7_reset_priv),
+};